Sources told Sveriges Radio (SR) that the Syrian-born man was one of the rebels' key weapons suppliers and that he had been bringing arms into the civil war-torn country for the last 18 months.
SR named the suspected arms dealer as Haytham Rahmeh and claimed he purchased weapons primarily in Libya, but also made purchases in Bosnia & Herzegovina. The arms have then been transported through Turkey and into the hands of rebels in Syria.
Raphaël Lefèvre, a researcher at Cambridge University who has interviewed Rahmeh, told SR that Rahmed has made frequent appearances among the Syrian opposition and has been open about sending weapons to the rebels via an organization known as the Commission for Civilian Protection.
"It's no secret that this group sends weapons to Syria," Lefèvre told SR.
For several years, Rahmeh was an imam at the Stockholm mosque located near Medborgarplatsen in the city centre. He also served as the chair of a European organization for imams before shifting his focus toward assisting Syrian rebels.
Thomas Tjäder, a security expert at the Swedish Agency for Non-Proliferation and Export Controls (Inspektionen för strategiska produkter - ISP) explained that smuggling weapons into Syria was a breach of Swedish arms control laws punishable by up to four years in prison.
The law applies to all Swedish citizens and registered residents, regardless of whether the weapons pass through Sweden or not, Tjäder told SR. The EU export embargo to Syria entails policing at national level, he explained, meaning that it was Sweden's job to probe potential breaches.
Nazir Hakim, head of the Commission for Civilian Protection, confirmed that Rahmeh has fundraised for the group and that some of the money collected went toward the purchase of weapons. He claimed, however, that the arms were bought inside Syria and not imported from Libya.
"We've purchased two boatloads of milk from Libya," he told SR.
SR quoted several sources, however, who claimed the group has imported weapons from Libya.